Aspen forests in some areas of Colorado have experienced widespread, severe, rapid dieback and mortality. This phenomenon, termed “sudden aspen decline,” has increased dramatically in recent years. In 2008, 553,000 acres of damage were recorded, over 17% of the estimated aspen cover type in Colorado. The southwestern and northwestern Colorado mountains are experiencing the worst damage.

Sudden Aspen Decline is caused by a warming climate which has been responsible for widespread droughts in the West. The climate change has weakened the Aspens that then allows the proliferation of insects and other parasites to attack and kill the weakened trees.

A tiny mark on the bark of one trunk prompts Angel Watkins to probe underneath with a knife, where she finds the wood is decorated by the convoluted track of a bronze poplar borer larva. While the inch-long larvae don’t usually kill aspen outright, their trails can weaken the trees and open new portals to fungal infections, which in turn form oozing bruises under the bark. On another tree, Worrall finds small cracks like those on the surface of a cookie, a clue that tunneling underneath has dried out the bark. Closer inspection turns up a bark beetle, no more than one-twelfth-inch long but capable, en masse, of cutting off the tree’s nutrient supply.

Why should we be concerned about a tree? The Los Angeles Times explains:

What foresters have termed Sudden Aspen Decline affects more than just aesthetics. Aspen trees provide a rich habitat for birds, elk, deer and other animals. The grasses that sprout under them — up to 2,000 pounds per acre — hold water that is needed by metropolitan areas. The trees do not burn easily and create natural firebreaks in forests already ravaged by the pine bark beetle — another parasite that is thriving because of global warming.

This is just another of the multifaceted damage global warming does and, sadly, there will be more.

Comments (2)

Eventually, perhaps in our lifetimes, people will conclude that billions of people and ultimately most higher-in-the-evolutionary-scale life forms will die because of what this generation has done and failed to do.

Have you seen this? There’s a brewing controversy about the climate change chapter in the new Superfreakonomics book where they basically take the climate change skeptics’ side (the authors deny this).